Mark Field isa member of the Intelligence and Security Committee and MP for the Cities of London and Westminster.

Anyone who has tried to talk about immigration in public will know that to proffer a view is to open oneself up to misrepresentation and endless vitriol. What has surprised me, however, since I launched Conservatives for Managed Migration on Tuesday, is the flood of positivity from email correspondents, Twitter users, commenters, journalists and fellow Conservatives alike, many of whom are delighted to hear our party discussing immigration in more measured tones.

To summarise, Conservatives for Managed Migration, is a group designed to promote a calm, reasoned debate about immigration both within and beyond the Conservative Party. I think it is vital we have this debate for two key reasons.

First, current immigration policy has implications for our nation and our economy. A cap on numbers is not only undeliverable but leads to an unhealthy focus on headline figures that is disconnected from reality. Since the government has precious few tools at its disposal to stem the tide of EU nationals, refugees and asylum seekers, efforts to decrease numbers inevitably rest on deterring many of the most desirable types of non-EU migrant – talented entrepreneurs, academics and business people. When government fails to meet its own targets, voter distrust is only reinforced.

Second, for years our nation’s politicians ducked honest discussion on immigration. Public resentment and anger, quite understandably, fast filled the policy vacuum. As that resentment has boiled over, so the political pendulum has swung erratically the other way. The rumbling threat of UKIP has only stiffened our resolve to talk tough on immigration. Nevertheless, the relentless focus on immigration by our party is beginning to seem to the outsider to border on near-obsession. The implicit message to the electorate is that Conservatives are fundamentally hostile to those who were not born here. This in spite of the fact that many immigrants to Britain demonstrate just the kind of enterprise and family values that should make them natural Tory voters.

Conservatives for Managed Migration’s aim is therefore two-fold – to try to move policy away from a focus on headline numbers and to attempt to change the tone of rhetoric over immigration.

Things we are not suggesting:

‘The UK should have an open-door policy’

In his ConservativeHome article yesterday, Sir Andrew Green of Migration Watch suggested the group’s whole argument is ‘based on a false choice between immigration control and an open economy.’ This is absolutely not the case, as my speech states explicitly. This is about finding policy that works, not sticking to one which, while superficially highly attractive, is undeliverable and damaging. Ironically, the objective of bringing ‘annual net migration down to the tens of thousands’ also makes us victims of our own success – the more our economy outperforms those of our European neighbours, so that more people want to come here and fewer leave, the more we are apparently “failing” to deliver a key policy.

‘The government should ‘go soft’ on its policies’

The Government has made some very sensible and pragmatic improvements to our migration system. Abuses have been cracked down on – bogus colleges, sham marriages, health tourists – and the Home Office is stopping the endless cycle of legal appeals for rejected applications. The government has also been striving to address some of the so-called ‘pull’ factors which have made Britain such an appealing destination for those exploiting our generous health and benefits systems. I am delighted by these efforts and have openly congratulated Ministers for all those measures, which were long, long overdue.

‘The cap should be dropped immediately’

This policy was in our 2010 manifesto and I appreciate the need for government to honour that, notwithstanding the pledge’s unintended consequences. But as we approach the next election, I believe we need to start articulating a more nuanced message which stresses that the complexity of this issue means that reform of the system cannot be judged on our delivery or otherwise of headline targets.

Sir Andrew Green suggested in his article yesterday that there is ‘no evidence of any serious difficulties for industry in the government’s current policy’. With respect to Sir Andrew, who is highly knowledgeable on immigration matters, he does not deal on a daily basis with the realities of the system. My parliamentary office does. Let me cite a few examples of cases I have been alerted to in the past 48 hours which suggest, at best, that there is a disconnect between policy and reality:

A Japanese professor of maritime law wishes to come to a British university on sabbatical for two years in 2015. He has been told that he can come for one year only and is not allowed to teach, even without payment (which is what he wants to do). Students are therefore being deprived of the expertise of another world authority.

A PhD student registered at one of China’s top universities wishes to spend a year studying in the UK for which she has a Chinese Government scholarship. She has been told that she can come for six months only, and now stands to lose her scholarship unless it is guaranteed that she can renew for a further six months.

A constituent who applied for a Tier 1 Entrepreneur Visa in 9 October 2012 who has been unable to access any further information regarding his case. He wishes to invest £50 000 in his business here but is reluctant to do so without having a confirmation or permission to stay.

The support I have had following Tuesday’s launch from top universities, entrepreneurs, constituents and business people would suggest that our group’s concerns are based on a little more than the ‘uncritical repetition of largely unfounded complaints’. Nevertheless, I accept the need for hard facts, which is why the group intends to publish research on the effect of the cap in the coming months.

Sir Andrew also suggested that the group left a gaping hole in our argument – EU migration. Again, I explicitly acknowledged in my speech that the government currently has minimal control over that element of the figures and cited it as one of the reasons why numbers of highly desirable prospective non-EU migrants are finding it hard to gain entry.

I must confess I find it absurd to witness each week the hoops we are making professional, English-speaking migrants jump through, while low-skilled EU migrants with no language proficiency are able to move to our shores with ease. It is for this reason that I made clear on Tuesday that I am incredibly supportive of the Prime Minister’s efforts to re-examine the rules governing free movement within the EU. That is just the kind of fresh policy focus we need.

This nation’s economic future depends on our taking the right approach towards those who wish to work, study and contribute here. All of that is what managed migration should mean. Neither an absence of controls, nor a raised drawbridge. Just sensible, rational, planned policy. Similarly, our party has always thrived most when it has adapted to or led change in Britain. We must remember that those who have or will come to our shores are not numbers – they are people. People who are hardly going to embrace our party us if we rarely seen to embrace them.

It is now time to move on from the Dutch auction that takes place at election time over immigration. It serves none of us well as politicians, and is certainly not in the interests of our nation as a whole. Conservatives for Managed Migration wishes to make a positive case for welcoming those who can make our country greater, and for putting in place realistic systems that can regain business and public trust. We believe that in doing so we can make both our nation, and our party, stronger. As Sir Andrew says, ‘Ill-founded criticism should have no place in a debate of such importance to our future’.